Cleaning concrete with muriatic acid can be a highly effective solution if used correctly, providing ultra-bright white concrete and removal of many types of stains. In one application, you can remove rust stains, oil stains, algae, and paint splatter with a quick chemical application followed by pressure washing.
Over time, it can destroy concrete as the acid weakens its structure. This will cause scaling, pitting, peeling, and cracking. If the acid wash gets into the soil, it will evaporate on the surface but remain beneath the surface (just like it does with concrete).
The most common acids used to clean concrete and bricks are hydrochloric acid (muriatic) or phosphoric acid. For many years it has been the standard cleaning method to prepare concrete for coatings installations, to remove stains of any type from concrete and to remove concrete slurry or efflorescence from bricks.
Scrub the acid solution: Once the solution is applied, lightly scrub it into the concrete with a push broom or long handled scrub brush. This helps to create a uniform etch of the concrete. Let the solution sit from 2 – 15 minutes while it continues to fizz and bubble.
But that's not all; chlorine bleach can also be used for cleaning the concrete driveway. Of course, you should dilute it with equal parts of water or a 1:1 ratio. With the mixture ready, spray it on the driveway, allowing it to sit for 10 minutes. Then, use a stiff brush before rinsing with clean water.
Muriatic acid can work wonders on filthy concrete. However, it shouldn't be used on penetrating sealers since it can damage these finishes. It might also damage some acrylic sealers, so test a small area if you're not sure.
When cleaning with basic pH chemicals such as sodium hypochlorite, you remove dirt, mold, and algae from surfaces easily, but do not get the brightening effects acidic pH chemicals, such as muriatic acid, provide. Muriatic acid can provide that bright white look that new concrete often has.
Muriatic acid is strong enough to etch concrete, but it can also cause severe injury and/or damage property when used improperly. Always wear protective clothing, rubber gloves, boots and goggles or a face shield when handling acid. Avoid breathing acid vapors.
Best for Driveways: Zep Driveway and Concrete Cleaner
Zep Driveway and Concrete cleaner is suitable for removing concrete stains, dirt, and oil marks. It's a budget-friendly choice coming in a four-pack of 1-gallon jugs. To use Zep Driveway and Concrete cleaner, mix the solution per the package directions.
Some common chemicals used for cleaning concrete include alkaline cleaners, acid cleaners, and enzymatic cleaners. Alkaline cleaners are effective for removing general dirt and grime, while acid cleaners are used for removing rust stains or mineral deposits.
Start by saturating the stained concrete surface with a product like ProClean Neutralizer™. This helps neutralize the acid stain and prepares the surface for thorough cleaning. 2. Gently scrub the neutralizer into the concrete using a soft nylon bristle brush, taking care to wear your spiked shoes during this process.
Muriatic acid: mix 3 to 4 parts water with 1 part acid, or follow label instructions for a 10% concentration (15% for hard, smooth concrete).
Phosphoric acid, trisodium phosphate, and muriatic acid all dissolve concrete. Phosphoric acid is the most common acid used for this task. Only use muriatic acid after removing all other acids.
Contractor's strength Muriatic Acid helps prevent cloudy water due to water hardness. Helpful for acid-washing your pool. Available in 2 one-gallon pack.
Mix one cup of TSP (trisodium phosphate) in a gallon of hot water, then pour the solution over the blemish. Let it soak in for at least 30 minutes, and then scrub with a stiff nylon brush. Finally, blast the spot with your hose set to the highest pressure.
Brush or spray on a 1:10 diluted mix of acid in water onto the surface, allow it to sit for up to 10 minutes, but no longer, then spray it with a solution of 1 cup ammonia in a gallon of water to neutralize the acid. Allow the surface to dry completely before applying paint or other treatments.
Sodium Bisulfate and muriatic acid could have a 5 year shelf life, however pH decreasers are acids, and a larger shelf life concern about pH decreasers is the strength of the container.
In fact, vinegar removes mold from concrete better than bleach. Bleach will only remove the top layer of mold, causing the mold to return.
Simply fill a spray bottle with equal parts water and vinegar (or water and baking soda), and add a little bit of liquid dish detergent. Spray the mixture on your concrete surface and let it sit for about 30 minutes. Then scrub and rinse your concrete.